Bolt-anchor.



IDATENT-ED Al i-1.23-

E. A. STULZ. BOLT ANCHOR.

APPLIOATION FILED JAN.16.1906.

L .5 m8 mA S UNITED STAT S PATENT option,

Specification of Letters Patent.

tamed April 23, 1907.

.. Application sanitar 1a. 1906." sash 1a. 296,268.

To all whom it may honeern: v Be it known that I, EDWARD ANTHONY STULZ,a citizen of the United States, and aresident of Avenel, New Jersey,have invented certain new and useful Improvements in Bolt-Anchors, ofwhich the following is a specification. 1 a

My invention relates to bolt-anchors such "as are inserted in holes madein walls of stone, brick, or other hard material for the purpose ofholding a bolt or screw engaged therein.

The object of the invention is to provide an expansible' anchor whichshall have a very complete and firm enga ement with the thread of thebolt and Wit the aperture in the wall in which it is placed.

A further object of the invention is to provide the anchor with means bywhich it is prevented from slipping into or through the aperture in thewal when the bolt isbeing engaged therein.

Further objects of the. invention will appear in the specification andbe pointed out in the claims. I

In the drawings, Figure lshows a bolt-anchor embodying my invention inoperative position. Fig. 2 is a perspective view of a section of thebolt-anchor. Fig. 3 is avertipral section through the bolt-anchor shownin 1 designates a wall in which is formed an apgrture 11, slightlytapered toward its rear en Y 2 2 designate bolt-anchor sections, shownas two in number, but which may of course be increased in number asdesired. As shown,

, the sections 2 are completely separated from sponding rccesses at theother.

each other; but it is obvious that this separation need only be made atthe rear end of the bolt-anchor to provide for its ex ansion as the bolt3 is driven therein, ach section 2, as shown, consists of a body portion21 of seinic lindric form, provided with projections 22 or engaging inthe sides of the aperture 11, and ofv a flange or head 23, extendinglaterally from thebody 21 at its forward end. at one side with a pluraity of lugs 24, adapt ed to engage in corresponding seats 25 in theadjacent section. As shown, the two sections are recisely similar, eachbeing provided with lugs 24'at one side and correface 26 of the section2 tapers from front to rear, so that when the sections are assembled'27, similar to those in a rifle-barrel.

The bod. 21'is also provided- The inner the bolt-anchor will haveaoonical bore. The face 26' is traversed by a plurality of grooves Itwill be seen that these are angularly disposed and that their pitch isopposite to that of the thread 31 o the screw or bolt to be engagedtherein and inthe present instance so asto be approximately at a rightangle with said t read. It will be also seen that the grooves thesections are assembied together the 27 in each section are 30 disposedthat when grooves will extend in continuous lines 7 around the bore ofthev anchor, as clearly.

shown in Fig. The bore of the anchor may be made. only sli htly largerthan the b0 y diameterof the olt 3 to be engaged therein, so that thethreadsfi'l will out deeply into the faces 26 of the anchor-sections,these being preferably made of soft metal.

It is cbvious'that the .chi or anymetal cut away from the faces 26o thebolt-anchor sections will find lodgment in thegrooves 27 and that these,in addition, make t possible to screw the bolt 3 therein without undueforce.

' In Fig. 1 of the drawingsl have shown the parts assembled, the bolt 3being entered within the anchor-sections 2, the head 32 of the boltengaging with a portion of a bracket 4, as shown. Where the wall 1 .ishollow or only of sufficient thickness so that the boltanchor nearly orquite extends therethrough, it is of great advantage to provide theanchor with the head or flange 23, as shown, tb revent its being forcedthrough the .wall w en the bolt is engaged th ein.

It is obvious that certain mechanical changes may be made'in my. deviceWithout departing from the spirit of the invention and that parts of thedevice may be useful without others.

What I claim isv 1 1. An expansible bolt-anchor having its boretraversed by a plurality of grooves pitched angularly from front to rearin a direction more nearly-longitudinalthan ciroumgereptial, forsubstantially the, purposes set ort 1.

2. In combination with a'threaded bolt an expansible bolt-anchor havinga conical bore traversed by a plurality of grooves pitched V angularlyfrom front to'rear in a direction opposite to that to the thread of thebolt.

3. An expansible bolt-anchor having its bore traversed by a pluralityof. singularly disposed grooves, an

a bolt engageable in a plurality of separate and similar sections:adjacent section said anchor, the grooves on the anchor and I togetherforming a body having a conical the threads of the bolt being greatlyinclined to each other. in

4. An expansible bolt-anchor composed of a plurality of separatesections together forml ing a body having a conical bore traversed by aplurality of angularly-disposed grooves, certain of the grooves in eachof said sections forming continuations of the grooves in an boretraversed by a lurality of angularlydisposed grooves, all oi the groovesin each of said sections forming continuations ofthe grooves in anadjacent section.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses EDW): R1) ANTHONY STULZ. Witnesses:

J. L. HALPiN,

.5. An expansible bolt-anchor composed of E. L. TOMLINS.

